Surface cyclone mask for the Antarctic Circumnavigation Expedition from December 2016 – March 2017 Data file(s): cyclone_mask_1hr.csv time_ISO8601: Date and time at the end of each time interval of one hour in the ISO 8601 format YYYY-MM-DDThh:mm:ss+00:00 [UTC] cyclone_flag: mask of occurrence (1) or not (0) of surface cyclones along the ACE track